How many blogs is too many?

I regularly post to three blogs. This one, which used to be work related, is now sort of miscellaneous. I try to keep my other blog @the.coalface, which is a multi-user WordPress blog hosted at my University, focussed on my reflections on my experiments with education technology. And I am a regular contributor to the Swansea Learning Lab community blog, where I typically re-post interesting items of e-learning inspiration and that I find in my daily trawl of my RSS feeds.